Method and apparatus that facilitates interference cancellation for control channels in heterogeneous networks

Abstract

Aspects are described for reducing interference in wireless systems. In a first embodiment, an uplink acknowledgment region associated with a macro cell is determined, and an assignment of uplink control resources is restricted to a region within the uplink acknowledgment region. A control signal is then transmitted to user equipment via the assignment of uplink control resources. In another embodiment, control signals are received from wireless terminals, which include desired uplink control signals associated with an access point base station, as well as interfering uplink acknowledgement signals associated with macro cells. The control signals may then be regenerated by cancelling the set of interfering signals from the control signals. The desired uplink control signals are then decoded.

What is claimed is: 
     
       1. A method that facilitates interference cancellation in heterogeneous networks, comprising:
 receiving a set of control signals from a plurality of wireless terminals, wherein the set of control signals includes desired uplink control signals associated with an access point base station, and wherein the set of control signals are transmitted within an uplink acknowledgement region associated with at least one macro cell; 
 identifying whether a set of uplink acknowledgement signals interferes with the set of control signals, wherein none of the interfering uplink acknowledgment signals are associated with a discontinuous transmission (DTX); 
 decoding the desired uplink control signals; and 
 regenerating the set of control signals, including cancelling the set of interfering uplink acknowledgment signals from the set of control signals, if the set of uplink acknowledgement signals interferes with the set of control signals. 
 
     
     
       2. The method of  claim 1 , further comprising determining that a particular acknowledgment signal is not associated with a DTX, and wherein the regenerating includes cancelling the particular acknowledgment signal. 
     
     
       3. The method of  claim 1 , wherein the identifying comprises determining a number of signals included in the set of interfering uplink acknowledgment signals, and wherein the regenerating includes cancelling the set of interfering uplink acknowledgment signals based on the number of signals. 
     
     
       4. The method of  claim 1 , wherein at least a portion of the method is performed by the access point base station. 
     
     
       5. The method of  claim 4 , wherein the access point base station is associated with a femto cell. 
     
     
       6. The method of  claim 4 , wherein the access point base station is associated with a pico cell. 
     
     
       7. An apparatus configured to facilitate interference cancellation in heterogeneous networks, comprising:
 a processor configured to execute computer executable components stored in memory, the components including: 
 a receiving component configured to receive a set of control signals from a plurality of wireless terminals, wherein the set of control signals includes desired uplink control signals associated with an access point base station, and wherein the set of control signals are transmitted within an uplink acknowledgement region associated with at least one macro cell; 
 a macro uplink component configured to identify whether a set of uplink acknowledgement signals interferes with the set of control signals, wherein none of the interfering uplink acknowledgment signals are associated with a discontinuous transmission (DTX); 
 a decoding component configured to decode the desired uplink control signals; and 
 a regeneration component configured to regenerate the set of control signals, including cancelling the set of interfering uplink acknowledgment signals from the set of control signals, if the set of uplink acknowledgement signals interferes with the set of control signals. 
 
     
     
       8. The apparatus of  claim 7 , wherein the macro uplink component is configured to determine that a particular acknowledgment signal is not associated with a DTX, and wherein the regeneration component is configured to cancel the particular acknowledgment signal. 
     
     
       9. The apparatus of  claim 7 , wherein the macro uplink component is configured to determine a number of signals included in the set of interfering uplink acknowledgment signals, and wherein the regeneration component is configured to cancel the set of interfering uplink acknowledgment signals based on the number of signals. 
     
     
       10. The apparatus of  claim 7 , wherein at least a portion of the apparatus is within the access point base station. 
     
     
       11. The apparatus of  claim 10 , wherein the access point base station is associated with a femto cell. 
     
     
       12. The apparatus of  claim 10 , wherein the access point base station is associated with a pico cell. 
     
     
       13. A computer program product, stored on a non-transitory computer-readable storage medium, that facilitates interference cancellation in heterogeneous networks, comprising code for:
 receiving a set of control signals from a plurality of wireless terminals, wherein the set of control signals includes desired uplink control signals associated with an access point base station, and wherein the set of control signals are transmitted within an uplink acknowledgement region associated with at least one macro cell; 
 identifying whether a set of uplink acknowledgement signals interferes with the set of control signals, wherein none of the interfering uplink acknowledgment signals are associated with a discontinuous transmission (DTX); 
 decoding the desired uplink control signals; and 
 regenerating the set of control signals, including cancelling the set of interfering uplink acknowledgment signals from the set of control signals, if the set of uplink acknowledgement signals interferes with the set of control signals. 
 
     
     
       14. The computer program product of  claim 13 , further comprising code for:
 determining that a particular acknowledgment signal is not associated with a DTX, and 
 cancelling the particular acknowledgment signal. 
 
     
     
       15. The computer program product of  claim 13 , further comprising code for:
 determining a number of signals included in the set of interfering uplink acknowledgment signals, and 
 cancelling the set of interfering uplink acknowledgment signals based on the number of signals. 
 
     
     
       16. The computer program product of  claim 13 , wherein at least a portion of the code is stored within the access point base station. 
     
     
       17. The computer program product of  claim 16 , wherein the access point base station is associated with a femto cell. 
     
     
       18. The computer program product of  claim 16 , wherein the access point base station is associated with a pico cell. 
     
     
       19. An apparatus configured to facilitate interference cancellation in heterogeneous networks, the apparatus comprising:
 means for receiving a set of control signals from a plurality of wireless terminals, wherein the set of control signals includes desired uplink control signals associated with an access point base station, and wherein the set of control signals are transmitted within an uplink acknowledgement region associated with at least one macro cell; 
 means for identifying whether a set of uplink acknowledgement signals interfere with the set of control signals, wherein none of the interfering uplink acknowledgment signals are associated with a discontinuous transmission (DTX); 
 means for decoding the desired uplink control signals; and 
 means for regenerating the set of control signals, including cancelling the set of interfering uplink acknowledgment signals from the set of control signals, if the set of uplink acknowledgement signals interferes with the set of control signals. 
 
     
     
       20. The apparatus of  claim 19 , wherein the means for identifying is configured to determine that a particular acknowledgment signal is not associated with a DTX, and wherein the means for regenerating is configured to cancel the particular acknowledgment signal. 
     
     
       21. The apparatus of  claim 20 , wherein the means for identifying is configured to determine a number of signals included in the set of interfering uplink acknowledgment signals, and wherein the means for regenerating is configured to cancel the set of interfering uplink acknowledgment signals based on the number of signals. 
     
     
       22. The apparatus of  claim 19 , wherein at least a portion of the apparatus is within the access point base station. 
     
     
       23. The apparatus of  claim 22 , wherein the access point base station is associated with a femto cell. 
     
     
       24. The apparatus of  claim 22 , wherein the access point base station is associated with a pico cell.